HBO, 7:00 p.m. ET

This new documentary about dyslexia might just as well have premiered on the Sundance Channel, because Robert Redford’s son James is the director – and one of the subjects at which he aims his camera is his own son, Dylan, who was diagnosed with dyslexia relatively early, at age 9. Rethinking Dyslexia explores new concepts in how to diagnose the disease – and, after that, how best to approach it.